   |`:envvar` |Environment variable that can override the config value and system property (before parsing) |
   |`:source` |Source or container (of reference type, e.g. atom/agent/promise etc.) of key/value pairs     |
 
-  ## Lookup function
+  ### Lookup function
 
   ```
   (fn [store key validator description value-parser default-value? default-value not-found-handler])->value

  "Like `let`, except in which the left hand side is a destructuring map, right hand side is the argument to key finder.
  Beside symbols, the destructuring map optionally supports `:defs` (symbols bound to key finders) and `:as` keys.

  ## Example

  ```
  (letval [{:defs [foo bar] ; foo, bar are key finders

(defn read-config
  "Read config file(s) returning a `java.util.Map` instance.

  ### Options

  | Kwarg           | Type     | Description                                  | Default                         |
  |-----------------|----------|----------------------------------------------|---------------------------------|
